The present invention relates generally to headlamp adjusters which are used to adjust the position of a reflector of an automobile headlamp assembly, and relates more specifically to a headlamp adjuster which includes an overload clutch mechanism.
Modern day headlamps for vehicles are engineered and designed to be aerodynamically efficient. In this regard, the headlamps are designed as sealed assemblies wherein the portion of the headlamp approximate the outer surface of the automobile is relatively stationary, and is aerodynamic.
A typical modem day headlamp assembly 12 is illustrated in a plan view seen as FIG. 1, and normally includes: a fixed housing 20, to which an outer headlamp lens 22 is affixed; a movable reflector 24, which is mounted within the fixed housing 20; and a stationary headlamp bulb (not shown), which is positioned within the movable reflector 24. Typically, the movable reflector 24 is mounted to the housing 20 by a universal or ball-type pivot 26 which is stationary, or fixed, on the housing 20.
A first pivot point 28 is disposed generally vertical, of the fixed pivot 26, and a second pivot point 30 is disposed generally horizontal of the fixed pivot 26. As such, the movable reflector 24 may be pivoted about the fixed pivot 26 in the vertical and horizontal planes to aim the headlamp beam. Adjustment mechanisms, or headlamp adjusters, 40 and 42 are typically provided at the first and second pivot points, 28 and 30, normally termed the vertical pivot and the horizontal pivot, and the headlamp adjusters 40 and 42 can be operated to effect movement of the reflector 24 in the vertical and horizontal planes.
The headlamp adjusters 40 and 42 are typically mounted to the housing 20 of the headlamp assembly 12 and have adjuster output shafts 44, 46 operatively connected to the movable reflector 24 by ball and socket type pivots, or the like, such that linear movement of the adjuster output shafts 44, 46 produces pivoting of the movable reflector in the vertical and horizontal planes. Specifically, each headlamp adjuster 40, 42 typically includes drive structure 48, 50 for receiving a tool, and typically the drive structure 48, 50 is precision geared to the adjuster output shaft 44, 46. The gearing provides that using the tool to rotate the drive structure 48, 50 causes linear translation of the adjuster output shaft 44, 46 and therefore adjustment of the position of the headlamp reflector 24.
Before an automobile is released to the consumer, the movable reflectors of the headlamp assemblies are adjusted to a desired position so that the headlamp beams are properly aimed in both the vertical and horizontal directions. To this end, headlamp adjusters are normally operated at the automobile assembly plant. Thereafter, if a movable reflector moves from its desired position, due, for example, to vibration, jarring, or the vehicle being in an accident, a mechanic can operate the headlamp adjusters in order to properly re-align the reflectors.
Typically, headlamp adjusters are structured such that over-travel of the adjuster shafts (i.e. 44 in FIG. 1) is not prevented. Over-travel of the adjuster shaft can cause breakage of the headlamp adjuster housing and/or the reflector to which the adjuster shaft is connected. Specifically, over-extension of the adjuster screw from the housing can damage the reflector, and over-retraction of the adjuster screw into the housing can cause the end of the adjuster screw to contact an interior wall of the housing and result in damage to the housing, such as cracking. A crack in the housing can permit moisture, dirt, etc. to enter the housing which is undesirable.
Accordingly, it is an object of an embodiment of the present invention to provide a headlamp adjuster which is structured such that over-travel of the adjuster output shaft is generally prevented.
Another object of an embodiment of the present invention is to provide a headlamp adjuster which includes an overload clutch mechanism which generally prevents over-travel of the adjuster output shaft.
Briefly, and in accordance with one or more of the foregoing objects, the present invention provides a headlamp adjuster which includes an adjuster output shaft which is engageable with a reflector of a headlamp assembly. The adjuster output shaft extends from a housing, and the headlamp adjuster is configured such that in an overload condition, the adjuster output shaft is prevented from translating substantially axially, thereby reducing the risk of damage resulting from over-travel of the adjustor output shaft.
Although a few embodiments and alternatives are discussed herein, it should be understood that modifications may be made thereto while staying within the scope of the present invention.